Flexible coupling.



H. B. LAPP.

FLEXlBLE COUPLING.

APPLICATION FILED nov.21. 1913.

1 ,1 85,208. Patented May 30, 1916.

awwwtom UNITED STATES PATENT OFFICE.

HARRY B. LAIP, OF TBENTON, NEW JERSEY, ASSIGNOR '10 DE LAVAL STEAMTURBINE COMPANY, OF YORK, N. Y., A CORPORATION OF NEW JERSEY.

FLEXIBLE COUPLING.

Specification of Letters Patent.

Patented May 30, -916.

To all whom it may concern Be it known that I, HARRY B. LAPP, 8. mtizenof the United States of America, and a resident of Trenton, in thecounty of Mercer and State of New Jersey, have invented certain new anduseful Improvements in Flexible Couplings, of which the following is aspecification.

This invention relates to flexible couplings designed to afford aslightly yielding driving connection between rotating shafts, rotatingwheels, and other rotating members, i. e., to afford such flexibilitythat the two members may be slightly out of line or at a slight angle toone another, or both; and the flexible connection herein described alsoprovides such resilience as suffices to absorb, and prevent unduetransmission of, sudden shocks.

My invention comprises a coupling member consisting of a short length ofwire cable provided at its ends with encircling sleeves whereby stressis applied efficiently to such cable section and whereby the couplingmember is held in place, and whereby an efficient sliding bearing isprovided between the coupling member and one of the two rotating membersbetween which power is to be transmitted; and also com prises otherfeatures as hereinafter set forth.

The objects of my invention are to improve flexible connectors of thetype referred to, and to make the same stronger, cheaper, more durable,and more easily manufactured; also to secure such members in place in animproved manner.

I will now proceed to describe my invention with reference to theaccompanying drawings, in which a flexible connector embodying myinvention is illustrated and the manner of use of such connector isillustrated, and in which two of the many possible means for securingsuch connector in place are illustrated.

In said drawings, Figure 1 shows a front elevation and partial sectionof a shaft cou- Dling embodying flexible connectors constructed inaccordance with my invention and embodying one of the means hereinafterdescribed for securing such connectors in place. Fig. 1 is a fragmentarytransverse section of one of the coupling disks, illustratin the groovestherein, the section of Fig. 1 being taken on the line :vm of Fig. 1.Fig. 2 shows a. section of-the shaft coupling shown in Fig. 1. Fig. 3shows a detail perspective elevation of one of .the flexible connectors.Fig. 4 shows an end view of such connector. F ig. 5 shows a fragmentaryend elevation of a shaft coupling embodying alternative means forsecuring the flexible connectors in place. Fig. 5 is a fragmentarylongitudinal section of the disk 4 shown in Fig. 5, the section of Fig.5 being taken on the line y-y of Fig. 5. .Fig. 6 is a fragmentarylongitudinal section of the construction shown in Fig. 5. Referringfirst to Figs. 1-4 inclusive numerals -1 and 2 designate rotary shafts,of which either may be a driving member and the other a driven member;and numerals 3 and 4 designate coupling disks mounted upon shafts 1 and2 respectively, and keyed thereto by keys 5 in the ordinary manner. Thecoupling disks 3 and 4 are provided with corresponding registering holes6 near their peripheries, such holes being adapted to receive thesleeves of the flexible connectors hereinafter described.

Figs. 3 and 4 show one of the connectors, comprising a short length ofwire cable 7 (shown in this instance as a helically wound cable ofordinary construction) provided at its two ends with sleeves or collars8 and 9, fitting closely over the ends of the said cable-section 7, andso serving to prevent separation of the strands of such cable section,the said sleeves 8 and 9 also fitting closely within the holes 6 of thecoupling disks 3 and 4'. These sleeves 8 and 9 may have a drive fit onthe ends of the cable section 7, or may be brazed thereon or weldedthereto. One of the sleeves, 8, preferably has a sliding fit with thehole 6 in which it fits, while the other sleeve, 9, instead of having asimilar sliding fit with the hole 6 in which it fits, is preferably heldin place within such hole by means such as hereinafter described. Itwill be apparent that, owing to the equal flexibility in all transversedirection; of the cable section 7, these flexible connectors permiteflicient transmission of motion from shaft 1 to shaft 2, or'vice versa,even though said shafts be out of line; also, for the same reason, andbecause sleeves 8 are free to slide in and out in the holes 6 in whichsuch sleeves 8 are seated, rotary motion may be transmitted efficientlyfrom shaft 1 to shaft 2, or vice versa, even though one of such shaftsbe at a slight angle with reference to the other of said shafts. It willalso be apparent that, since there is considerable clearance between theadjacent ends of sleeves 8 and 9, and between the sides of the cablesection 7 and the sides of the holes 6, any sudden shocks experiencedduring transmission of motion from shaft 1 to shaft 2, or vice versa,will be absorbed in large measure by lateral flexing of cable sections7. In practice, the strands of these cable sections 7 are composed ofsteel or other metal having considerable resilience, so that the shaftcoupling herein described provides a spring-connection between the oneshaft and the other.

In the arrangement for holding the con nectors in place, illustrated inFigs. 1 and 2, the coupling disk 4 is provided, on its outside face,with a groove 10 of less width than the diameter of the holes 6, andwith another groove 11 of greater width than the groove 10, but of lessradius than the radial distance from the center of the shaft to theoutside of the holes 6; and the sleeves 9 are provided with projectingportions 12 having notches 13 corresponding to the groove 11.; and whenthe several connectors are in place, a spring keying wire 14 is insertedin the groove 11 and in the notches 13, such keying wire holding thesleeves 9 against axial motion.

In the alternative construction illustrated in Figs. 5 and 6, the disk 4is provided with a groove 10 of about the width of holes 6, and withother grooves 15, and spring collars 16, open on one side and fittingwithin the grooves 15, and adapted to fit also within other grooves 16,in the sleeves 9, are sprung over said sleeves after the connectors havebeen inserted.

By either of these constructions the flexible connectors are held inplace against longitudinal motion with respect to disk 4. But it will beunderstood that I do not limit myself to any particular means forholding these flexible connectors against longitudinal motion withrespect to one of the disks or members between which rotary motion is tobe transmitted, nor do I limit myself to the securing of the connectorsagainst longitudinal motion; though in general it is better to securethe connectors against longitudinal motion with reference to on of saiddisks or rotary members.

I am aware that heretofore various forms of shaft connectors have beenemployed, some comprising laminated structures consisting of thinflexible metal plates and some comprising rubber or other flexiblenon-metallic material. It is evident that laminated structurescomprising thin metal plates are not equall flexible in all directions,and that lubrication of the laminae is desirable. It is obvious thatstructures comprising rubber or other non-metallic material are notdurable. So far as I am aware my structures hereinbefore set forth arethe first structures wherein motion is transmitted between rotatingmembers by means of flexible connectors comprising short sections ofstranded cable arranged non-axially, i. e., set well away from the axisof rotation, and transmitting motion by lateral stress rather than bytorsional stress. Flexible shafts composed of stranded cable andtransmitting motion by torsional stress are, of course, quite common;but in such flexible shafts the two ends of such shafts are coaxial withthe rotary members between which motion is transmitted and motion istransmitted by torsional stress on the flexible cable rather than bylateral stress, as in my construction. Where such flexible shafts areemployed, since such shafts are at their ends (and, except for droop,elsewhere) close to the axis of rotation, they are located relativelydisadvantageously for the transmission of rotary motion.

I believe it to be essential that, in order that the flexible connectorsherein described may transmit motion without undue flexure the distancebetween the adjacent ends 0 the-confining sleeves or bushings of eachsuch connector be spaced apart by a distance not greater than four timesthe diameter of the cable; and preferably such distance is even less,and not more than twice the diameter of the cable.

What I claim is 1. A flexible coupling such as described comprisingrotary driving and driven members and one or more flexible connectorstherebetween, and arranged to transmit rotary motion from one to theother, and each comprising a short length of stranded cable connected atits ends to said driving and driven members and arranged approximatelyparallel to the axes of said driving and driven members, but well awayfrom the centers of said driving and driven members, power beingtransmitted from the driving to the driven member through saidconnectors, by lateral stress on said connector or connectors, saidconnector or connectors having each a longitudinal sliding connectionwith one of said driving and driven members.

2. A flexible coupling such as described comprising rotary driving anddriven members and one or more flexible connectors therebetween, andarranged to transmit rm tary motion from one" to the other, and eachcomprising a' short length of stranded cable connected at its ends tosaid driving and driven members and arm (1 approximately parallel to theaxes 0 said driving and driven members, but well away from the centersof said driving and driven members, power being transmitted from thedriving to the driven member through said connectors, by lateral stresson said connector or connectors, said connector or connectors havingeach a longitudinal sliding connection with one of said driving anddriven members, and being held against longitudinal motion withreference to the other of said driving and driven members.

3. A flexible coupling such as described comprising rotary driving anddriven members and one or more flexible connectors therebetween, andarranged to transmit rotary motion from one to the other, and eachcomprising a short length of stranded cable having at its ends confiningsleeves fitting within holes in said driving and driven members whichare eccentric to the axes of rotation of said driving and drivenmembers, power being transmitted from the driving to the driven memberthrough said connector by lateral stress on said connector orconnectors, one of the confinin sleeves of each such connectors having asli ing con nection with one of said driving and driven members.

4. A flexible coupling such as described comprising rotary driving anddriven members and one or more flexible connectors therebetween, andarranged to transmit rotary motion from one to the other, and eachcomprising a short length of stranded cable having at its ends confiningsleeves fitting within holes in said driving and driven members whichare eccentric to the axes of rotation of said driving and driven members, power being transmitted from the driving to the driven memberthrough said connector by lateral stress on said connector orconnectors, one of the confining sleeves of each such connectors havinga sliding connection with one of said driving and driven members, theother confining sleeve of each such connector or connectors being heldagainst longitudinal motion with respect to the other of said drivingand driven members.

5. A flexible coupling such as described comprising rotary driving anddriven members and one or more flexible connectors therebetween, andarranged to transmit rotary motion from one to the other, and eachcomprising a short length of stranded cable provided at its ends withconfining sleeves, the adjacent ends of said confining sleeves beingspaced apart, said sleeves fitting within eccentric apertures in saiddriving and driven members, the said apertures of greater diameter thanthe diameter of said stranded cable whereby space is provided forlateral play of said cable connector or connectors.

In testimony whereof I have signed this HARRY B. LAPP.

Witnesses:

C. P. WALLER, HENRY J. HANGLEK.

